| ILIMIA, LLC Rosemont Structural | Chesapeake | VA | 20–99 | ◐ LIKELY ACTIVE |
| IFImpact Fab | Holland | MI | 20–99 | ◐ LIKELY ACTIVE |
| IIImpact Industries, Inc. | North Ridgeville | OH | 20–99 | ◐ LIKELY ACTIVE |
| IIImperial Iron Works, LLC | Las Vegas | NV | — | ◐ LIKELY ACTIVE |
| ISImperial Stamping Corporation | Elkhart | IN | 20–99 | ◐ LIKELY ACTIVE |
| IEImpres Engineering Services, LLC | Holland | MI | — | ◐ LIKELY ACTIVE |
| IHIMR - Hayden | North Vernon | IN | 20–99 | ◐ LIKELY ACTIVE |
| IAIN Acquisition LLC | Hudson | MA | 20–99 | ◐ LIKELY ACTIVE |
| IMIncremental Machine LLC | Baltimore | MD | — | ◐ LIKELY ACTIVE |
| IWIndependent Welding & Machine LLC | Cocoa | FL | — | ◐ LIKELY ACTIVE |
| IMIndiana Mobile Welding LLC | Cicero | IN | — | ◐ LIKELY ACTIVE |
| IIndianapolis | Indianapolis | IN | 100–499 | ◐ LIKELY ACTIVE |
| ICIndian Creek Fabricators INC. | Tipp City | OH | — | ◐ LIKELY ACTIVE |
| I1Indidge 1 Artistic Metal Works LLC | Independence | MO | — | ◐ LIKELY ACTIVE |
| ISIndustial Steel Constructors | Denham Springs | LA | 1–19 | ◐ LIKELY ACTIVE |
Industrial Automation LLC - Alabama | Montgomery | AL | 1–19 | ◐ LIKELY ACTIVE |
| ICIndustrial Consortium INC | Lancaster | PA | — | ◐ LIKELY ACTIVE |
| IDIndustrial Design Manufacturing LLC | Mount Sterling | KY | — | ◐ LIKELY ACTIVE |
| IEIndustrial Engineering Manufacturing Co, INC | Foxboro | MA | — | ▲ REPORTED CLOSED |
| IFIndustrial Fabrication LLC | Bridgman | MI | 20–99 | ◐ LIKELY ACTIVE |
| IMIndustrial Manufacturing Services | Lancaster | SC | 20–99 | ◐ LIKELY ACTIVE |
| IMIndustrial Metal Enterprises LLC | Blackfoot | ID | 20–99 | ◐ LIKELY ACTIVE |
| IMIndustrial Metal Works LLC | Newtown | CT | — | ◐ LIKELY ACTIVE |
| IPIndustrial Products | Coon Rapids | MN | 20–99 | ◐ LIKELY ACTIVE |
| IRIndustrial Resources, Inc. | Fairmont | WV | 20–99 | ◐ LIKELY ACTIVE |
| IRIndustrial Rigging Services of Central Texas | Hewitt | TX | 20–99 | ◐ LIKELY ACTIVE |
| ISIndustrial Steel South LLC | Rockledge | FL | 1–19 | ◐ LIKELY ACTIVE |
| ISIndustrial Stripping Services LLC | Grand Rapids | MI | 20–99 | ◐ LIKELY ACTIVE |
| ITIndustrial Tank & Containment INC | Brookfield | OH | — | ◐ LIKELY ACTIVE |
| ITIndustrial Technologies Group ITG Bartell | Rome | NY | 100–499 | ◐ LIKELY ACTIVE |
| ITIndustrial Technologies Group ITG CA Design Raleigh | Raleigh | NC | 20–99 | ◐ LIKELY ACTIVE |
| ITIndustrial Technologies Group ITG Field Controls | Kinston | NC | 100–499 | ◐ LIKELY ACTIVE |
| ITIndustrial Technologies Group ITG Precision Engineering | Uxbridge | MA | 20–99 | ◐ LIKELY ACTIVE |
| ITIndustrial Technologies Group ITG Versatile Mold and Design | Rutledge | GA | 20–99 | ◐ LIKELY ACTIVE |
| ITIndustrial Technologies Group ITG WakefieldNashua | Nashua | NH | 100–499 | ◐ LIKELY ACTIVE |
| IIndy | Indianapolis | IN | 1–19 | ◐ LIKELY ACTIVE |
| IIIN-FAB Inc. | Bedford | IN | 20–99 | ◐ LIKELY ACTIVE |
| IDInfastech, Decorah MFG (IND, EF) Emhart Tecknologies LLC | Decorah | IA | 100–499 | ◐ LIKELY ACTIVE |
| IDInfinity Drain LTD | Amityville | NY | 100–499 | ◐ LIKELY ACTIVE |
| IFInfrastructure Fabrication LLC | Bath | PA | — | ◐ LIKELY ACTIVE |
| ITInlet Tools, INC | Conneautville | PA | — | ◐ LIKELY ACTIVE |
| IWInnisfallen Works | Springfield | OH | 20–99 | ◐ LIKELY ACTIVE |
| ILInnova LLC | Grapevine | TX | — | ◐ LIKELY ACTIVE |
| IFInnovation First Manufacturing, Inc. | Greenville | TX | 20–99 | ◐ LIKELY ACTIVE |
| IMInnovations Manufacturing INC | Redding | CA | — | ◐ LIKELY ACTIVE |
| IEInnovative Engineered Solutions | Wilmington | OH | 20–99 | ◐ LIKELY ACTIVE |
| IMInnovative Mechanical Solutions LLC- IMECH | Houston | TX | 20–99 | ◐ LIKELY ACTIVE |
| IDInrock Drilling Systems | Houston | TX | 20–99 | ◐ LIKELY ACTIVE |
| ICInsingerMachine Company | Philadelphia | PA | 20–99 | ◐ LIKELY ACTIVE |
| IEInstitutional Equipment INC | Bolingbrook | IL | — | ◐ LIKELY ACTIVE |